# CVE-2026-92288: lemonldap-ng: Lemonldap::NG::Portal versions from 2.20.0 before 2.21.6, from 2.22.0 before 2.23.4 for Perl allow unauthenticated OA...

CVE-2026-92288 is fixed in 11 products on 1 platform, first by FEDORA-2026-33DCAB55B4, released September 25, 2026. It is not reported as exploited. Patch Radar priority: Urgent.

- Web page: https://patchblox.com/security/cve/CVE-2026-92288
- Priority: Urgent
- CVSS: 9.1 (critical)
- EPSS: 0.0044
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 25, 2026

## Description

Lemonldap::NG::Portal versions from 2.20.0 before 2.21.6, from 2.22.0 before 2.23.4 for Perl allow unauthenticated OAuth2 token introspection because checkEndPointAuthenticationCredentials does not verify the client secret of a public Relying Party.  checkEndPointAuthenticationCredentials() skips the secret comparison for a Relying Party marked public and still returns the authentication method deduced from the request, client_secret_basic or client_secret_post. introspection() rejects a caller only when that method is missing or none, so a request carrying a public client_id and an arbitrary or empty secret passes the endpoint's authentication check.  An attacker who holds an access token and knows the client_id of any public Relying Party can confirm the token is active and read its metadata, including scope, audience, expiry and the sub claim. The sub claim is computed with the calling Relying Party's user identifier attribute, so an attacker can translate a user identifier from one Relying Party to another, defeating per-client and pseudonymous identifiers.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | lemonldap-ng Debian 13.5 (trixie) | 2.21.2+ds-1+deb13u4 | [DEBIAN-CVE-2026-92288](https://patchblox.com/security/data/fix/linux/debian-cve-2026-92288.md) | Sep 27, 2026 |
| Linux | lemonldap-ng Debian 14 | 2.23.4+ds-1 | [DEBIAN-CVE-2026-92288](https://patchblox.com/security/data/fix/linux/debian-cve-2026-92288.md) | Sep 27, 2026 |
| Linux | lemonldap-ng Fedora 43 | 2.23.4-1.fc43 | [FEDORA-2026-33DCAB55B4](https://patchblox.com/security/data/fix/linux/fedora-2026-33dcab55b4.md) | Sep 25, 2026 |
| Linux | lemonldap-ng-common Fedora 43 | 2.23.4-1.fc43 | [FEDORA-2026-33DCAB55B4](https://patchblox.com/security/data/fix/linux/fedora-2026-33dcab55b4.md) | Sep 25, 2026 |
| Linux | lemonldap-ng-doc Fedora 43 | 2.23.4-1.fc43 | [FEDORA-2026-33DCAB55B4](https://patchblox.com/security/data/fix/linux/fedora-2026-33dcab55b4.md) | Sep 25, 2026 |
| Linux | lemonldap-ng-fastcgi-server Fedora 43 | 2.23.4-1.fc43 | [FEDORA-2026-33DCAB55B4](https://patchblox.com/security/data/fix/linux/fedora-2026-33dcab55b4.md) | Sep 25, 2026 |
| Linux | lemonldap-ng-handler Fedora 43 | 2.23.4-1.fc43 | [FEDORA-2026-33DCAB55B4](https://patchblox.com/security/data/fix/linux/fedora-2026-33dcab55b4.md) | Sep 25, 2026 |
| Linux | lemonldap-ng-manager Fedora 43 | 2.23.4-1.fc43 | [FEDORA-2026-33DCAB55B4](https://patchblox.com/security/data/fix/linux/fedora-2026-33dcab55b4.md) | Sep 25, 2026 |
| Linux | lemonldap-ng-portal Fedora 43 | 2.23.4-1.fc43 | [FEDORA-2026-33DCAB55B4](https://patchblox.com/security/data/fix/linux/fedora-2026-33dcab55b4.md) | Sep 25, 2026 |
| Linux | lemonldap-ng-selinux Fedora 43 | 2.23.4-1.fc43 | [FEDORA-2026-33DCAB55B4](https://patchblox.com/security/data/fix/linux/fedora-2026-33dcab55b4.md) | Sep 25, 2026 |
| Linux | lemonldap-ng-test Fedora 43 | 2.23.4-1.fc43 | [FEDORA-2026-33DCAB55B4](https://patchblox.com/security/data/fix/linux/fedora-2026-33dcab55b4.md) | Sep 25, 2026 |
| Linux | lemonldap-ng-uwsgi-app Fedora 43 | 2.23.4-1.fc43 | [FEDORA-2026-33DCAB55B4](https://patchblox.com/security/data/fix/linux/fedora-2026-33dcab55b4.md) | Sep 25, 2026 |
| Linux | perl-Lemonldap-NG-SSOaaS-Apache-Client Fedora 43 | 2.23.4-1.fc43 | [FEDORA-2026-33DCAB55B4](https://patchblox.com/security/data/fix/linux/fedora-2026-33dcab55b4.md) | Sep 25, 2026 |

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Data as of 2026-11-09T13:31:49Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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